“Mosques that are funded by foreign governments should not get a tax break in the US.”
Unfortunately, your proposal would have to be applied universally, and it would be terrible for Catholicism in the U.S.
There may be management of the money within the Vatican, but money comes in there from the congregations. It is redistribution.
The Saudi State funds the expansion of Islam in the West to appease the Wahabi terrorists who captured Mecca in the 1970s.
Catholic Churches in the U.S. are funded by foreign governments? I don't think so.